Adobe Acrobat Reader for previewing pdf

It should be possible to create a plugin that would display PDFs in such a way that the Acrobat plugin would be used.

From our perspective, we like Google Docs better because it works across platforms, Windows, Mac, Linux, and mobile. Many or most users of those non-Windows platforms won't have Acrobat Reader, or its plugin.

Also, I do seem to remember the Google Docs Viewer having the ability to search within a PDF.

Your site seems to use a pretty simple embed tag to load the user's PDF reader plugin.

It would be pretty easy to write an Omeka plugin that outputs an embed or object tag that would cause a browser plugin to be used for reading PDFs.